Wire corrugator

ABSTRACT

An apparatus for corrugating cable drain wires has an individual motor for each of a plurality of pairs of corrugating rolls mounted around a polygonal frame and having a common speed control.

United States Patent 1 Chrisman et al.

[ 51 Feb. 27, 1973 WIRE CORRUGATOR Inventors: Willis L. Chrisman, Fairmont;

Walter R. Ring, Sr., Elm Montpeliter, both of Ind.

Assignee: Anaconda Wire and Cable Company, New York, N.Y.

Filed: Feb. 1, 1971 Appl. No.: 111,416

U.S. Cl ..72/l96, 72/268 Int. Cl ..B2lc 23/24 Field of Search ..72/l7, 256, 268, 270, 187,

[56] References Cited UNITED STATES PATENTS 3,531,962 10/1970 Menasoff ..72/17 3,303,529 2/1967 Boggs ..425/1 14 1,981,547 11/1934 Harwood ..3 18/79 3,476,157 11/1969 DeWulf ..l40/105 Primary Examiner-Lowell A. Larson Attorney-Victor F. Volk [57] ABSTRACT An apparatus for corrugating cable drain wires has an individual motor for each of a plurality of pairs of corrugating rolls mounted around a polygonal frame and having a common speed control.

11 Claims, 5 Drawing Figures WIRE CORRUGATOR BACKGROUND OF THE INVENTION In the manufacture of electric cables, such as the cables described in US. Pat., No. 3,474,189, corrugated or undulatory drain wires are embedded in the cables jackets by paying them into an extruder, in spaced positions around the cable core, during the jacket extrusion operation. This operation demands reliability far beyond the reliability associated with an independent corrugating operation because any failure or interruptions of the corrugating wires will require the shutting down not only of the corrugating apparatus, but of the entire extrusion process. Such a contingency would be very costly, not only because of down time, but because a shut down would inevitably require the scrapping of substantial quantities of cable. The simultaneous corrugating and paying off of a plurality of drain wires in spaced positions around a cable core has moreover, presented certain problems which, until the present invention, where not satisfactorily solved. The principal of these problems stem from the fact that the corrugated wires are hard to handle and arrange into proper spacing, because when tension is applied to the wires, it does not necessarily serve to pull them into the desired line of travel, but serves rather to open up the corrugations. This is in itself unacceptable and is complicated by the fact that because of unavoidable variations in wire gage and stiffness, equal tension changes do not open the corrugations equally. When different size cables are being manufactured correspondingly different depths or amplitudes of corrugation are required for all the wires. It would be disadvantageous if the corrugating rolls must be removed and replaced to effect the change in amplitude, but, prior to the present invention there has been no way of changing corrugations without changing the rolls.

SUMMARY Our apparatus for corrugating drain wires for a cable core that is being paid into an extruder comprises a polygonal frame mounted across the line of advance of the core, so that the core passes through the frame. A plurality of pairs of corrugating rolls are mounted on the frame in spaced positions around the core'along with individual torque assist motors for each pair of rolls, means directing the wires between the rolls of each pair where they are corrugated, and means guiding the corrugated wires into spaced positions around the core in the same order as the pairs of rolls.

The corrugating rolls comprise radial teeth which, in a preferable embodiment, substantially exceed in length the minimum depth of corrugation of the wires. The apparatus then comprises means for limiting the depth of intermeshing of the teeth thereby limiting the amplitude of the corrugations, as desired.

Preferred embodiments also include means, such as means comprising fluid pressure cylinders, for separating the rolls of each pair for the purpose of threading in the wires and thereafter returning the rolls to their intermeshed positions. Gang means, such as means for controlling the voltages of all the motor armatures, are provided in our apparatus for controlling the speed of the rolls and the speeds of individual pair of rolls can be adjusted to the other pairs by means such as individual field voltage controls. The gang speed control means is advantageously made to respond automatically to changes in the speed of advance of the core.

In one preferred embodiment our apparatus for corrugating drain wires for a cable core being paid into an extruder comprises a polygonal frame that is mounted across the line of advance of the core so that the core passes through the frame. A plurality of D.C. motors with their armaturcs connected in parallel are mounted on the frame in spaced positions around the core with a toothed corrugating roll supported on the shaft of each motor. Means are provided for retractably mounting a like plurality of toothed idler rolls in intermeshing relation with the corrugating rolls means for separating and intermeshing the corrugating and idler rolls, which may advantageously comprise the same plurality of fluid pressure cylinders, each comprising a piston actuating one of the separating and intermeshing means. Valve means direct pressurized fluid into each of the cylinders so as to either separate or intermesh the rolls which are limited by stops in their movement toward intermeshing so as to achieve a preselected amplitude of corrugations. Gang means are included to control the speed of all the motors by varying the armature voltage. In a preferred embodiment of our apparatus this speed control responds automatically to changes in the speed of advance of the core.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an overall pictorial view of the apparatus of our invention.

FIG. 2 shows a plan view of one of the corrugating units of our invention.

FIG. 3 shows a schematic wiring diagram of electrical components of our invention.

FIG. 4 shows a side view at 44 of FIG. 2.

FIG. 5 shows a detailed section of the stop 57 of FIG. 2.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT:

Referring first to FIG. 1, our apparatus is indicated generally by the numeral 10. A cable core 11 is pair continuously through the center of a hexagonal frame 12 supported on vertical members 13 which are bolted to a concrete floor or otherwise firmly secured upstream of an extruder head 14 wherein a polymeric jacket is extruded over the core 11. Six pairs 16 of corrugating rolls are mounted symmetrically upon the frame 12, although it will be understood that our invention is useful for the application of numbers of wires other than 6, around to the core 11 and, indeed, is not limited necessarily to cases where the distribution of the wires around the core is symmetrical.

The core 11 is supported by a roller 17 mounted on the frame 12 at the upstream end of the apparatus 10, and is urged to advance by a capstan l8 downstream of the extruder head 14. The capstan 18 may, indeed, be considerably separated from the head 14 to provide for manufacturing units such as cooling trough which are not shown in the drawing, but are old in the cable making arts. Regardless of the remoteness of the capstan 18 from the head 14, however, the speed of the core 11 is determined by the capstan 18. Six drain wires 19, to be corrugated, are paid from supply stations, not shown, through guiding eyelets 21,22 between the roll pairs 16,

tension sensing mechanisms 23, and guide rolls 24, into the extruder head 14 where they become embedded in the cable jacket 15.

The pairs 16 are seen, more particularly in FIG. 2, each to comprise a fixedly mounted toothed roll 26 and an intermeshing idler roll 27. The roll 26 has a plurality of radial teeth 28 and the roll 27 has corresponding teeth 29 which intermesh to form undulations or corrugations 31 in the wires 19. As shown in the drawing, the length of the teeth 28,29 exceed the length required for certain desired amplitudes of the corrugations 31 so that by changing the degree of intermeshing of the rolls 26,27 different corrugations may be selected at will without changing the rolls, as will be explained. In order to thread the wires 19 through the pairs 16, the idler rolls 27 can be retracted or separated. To this end the rolls 27 are mounted in brackets 32 pivoted on pins 33 to mesh with the rolls 26 when urged by pistons 34 of pneumatic cylinders 36 of which there is one for each pair 16 of rolls. All of the cylinders 36 are connected through high pressure piping 37 to a source of compressed air, not shown, so that all the rolls 27 can be intermeshed with the rolls 26 or retracted by the action of valves 38. The rolls 26 are driven by D.C. motors 39 acting through speed reducers 41 at a speed that can be adjusted to pay corrugated wires at the speed of the take-up capstan l8.

Wiring of the motors 39 is shown in FIG. 3. Electrical power from A.C. source 42 is converted to D.C. by means of a conventional control rectifying circuit 43 to supply both fields 44 and armatures 45 of the motors 39. A gang control of the voltages of the armatures 44 through a conventional firing circuit 46 may be obtained manually by means of a variable resistor 47 or a tachometer controlled circuit 48 responsive to the speed of the capstan 18. Conventional pushbutton control of relay switches 49,50 is employed to switch to manual or tachometer gang control of the motor speeds. In addition the field resistances 44 are in series with easily accessible, manually adjustable rheostats l for fine adjustment of the speed of any individual motor.

In order to control the amplitude of the corrugations 31, plates 52 comprised in the brackets 32 are provided with shoulders 53 which abut one of three bolts 54, 55, S6 of stops 57 when the roll 27 is in mesh with the roll 26. The length of projection of the bolts 54, 55, 56 are adjusted differently to provide the desired depth of intermeshing of the teeth 28,29 and can be set to turn the desired bolt toward the shoulder 53 by rotating a disc 58 on its pin 59 until it is caught in position by means of a ball and spring 61 engaging a notch 62, as shown in detail in FIG. 5.

As has been mentioned hereinabove, tension on the wires 19 would have the effect of pulling out the corrugations. To prevent any such occurrence, the wire leaving the rolls 26,27 passes over a guide roller 63 the surface of which, due to the hexagonal shape of the frame 12, is substantially normal to a radius through the core 11. On leaving the roller 63 the corrugated wires pass through the tensioning sensing mechanisms 23 as shown in detail in FIG. 4. This tension mechanism comprises a bracket plate 64 fixed to the frame 12 and mounting an adjustably fixed roller 66 and a limit switch 67 in the motor circuit. To the plate 64 is hinged, at 68, a rigid flat bar 69 mounted another roller 71. The corrugated strand 19 is threaded over the roller 63, over the roller 71, and under the roller 66, so that any tension in the strand tends to press the. bar 69 against a spring 72 and pin 73 of the limit switch 67 which is normally open. Different compression springs 72 can be used to compensate for different effects of the weight of the roller 71 and bar 69 at different locations around the frame 12. The guide rollers 24 then guide the wires into the head 14.

OPERATION In the operation of the apparatus of our invention all the discs 58 are first rotated to project the appropriate bolt 54, 55, or 56 for the desired amplitude of the corrugation 31. Valves 38 are turned to separate the rolls 26 and 27 and wires 19 are threaded through the apparatus and into the extruder head 14, along with the core 11. The capstan 18 or other pulling means are energized so that straight wire is pulled at a steady rate through the apparatus 10. The valves 38 are then operated manually to intermesh each of the pairs 16 of rolls and corrugate the wires. The speed of the motors is adjusted by means of the rheostats 51 to be very slightly in excess of the required speed so that they are occasionally stopped by the action of the limit switches 67 when slack develops in the corrugated wires. Since the corrugated wires are in proper positions relative to the core at the instant they are corrugated, and this constitutes an important feature of our invention, they only require to be brought radially closer to the core in the final step of manufacturing a cable and are in no danger of having the shape of the corrugations distorted by further positioning steps.

We have invented a new and useful apparatus of which the foregoing description has been exemplary rather than definitive and for which we desire an award of Letters Patent as defined in the following claims.

We claim:

1. An apparatus for corrugating drain wires for a cable core being paid into an extruder comprising,

A. a polygonal frame mounted across the line of advance of said core, said core passing horizontally through said frame,

B. a plurality of pairs of corrugating rolls mounted on said frame in spaced positions around said core,

C. payoff means for a like plurality of drain wires in fixed positions relative to said frame,

D. means directing said wires between the rolls of said pairs, said rolls corrugating said wires, and

E. means guiding said corrugated wires into said extruder in spaced positions around said core having the same order as the positions of the respective pairs of rolls for each wire.

2. The apparatus of claim 1, wherein said rolls comprise radial teeth substantially exceeding in length the minimum depth of corrugation of said wires and said apparatus comprises means for limiting the depth of intermeshing of said teeth to any one of a plurality of preset positions, thereby limiting the amplitude of said corrugations to a predetermined value.

3. The apparatus of claim 1, comprising compressed air means for separating the rolls of each of said pairs for threading said wires therebetween and thereafter returning said rolls to intermeshed positions.

4. The apparatus of claim 1, comprising individual motors mounted on said frame driving each of said pairs of rolls.

5. The apparatus of claim 4, comprises gang means for controlling the speed of said rolls.

6. The apparatus of claim 5, wherein said speed controlling means comprises a voltage control of the armatures of said motors.

7. The apparatus of claim 6, comprising means for varying the speed of each of said pairs of rolls relative to the remaining pairs.

8. The apparatus of claim 7, wherein said speed varying means comprises motor field voltage controls.

9. The apparatus of claim 4, comprising gang speed control means for said rolls automatically responding to changes in the speed of advance of said core.

10. An apparatus for corrugating drain wires for a cable core being paid into an extruder comprising:

A. a polygonal frame mounted across the line of advance of said core, said core passing horizontally through said frame,

B. a plurality of DC. motors mounted on said frame in spaced positions around said core, with their armatures connected in parallel,

C. a like plurality of toothed corrugating rolls, each mounted to be driven by one of said motors,

D. a like plurality of toothed idler rolls mounted in intermeshing relation with said corrugating rolls, E. means for separating and intermeshing said corrugating and idler rolls,

F. A like plurality of fluid pressure cylinders mounted on said frame each comprising a piston actuating one of said separating and intermeshing means,

G. valve means directing pressurized fluid into each of said cylinders,

H. a like plurality of adjustable stops limiting the movement toward intermeshing of said idler rolls, and

1. gang means for controlling the speed of all of said motors by varying the armature voltage.

11. The apparatus of claim 10, wherein said speed controlling means automatically responds to changes in the speed of advance of said core. 

1. An apparatus for corrugating drain wires for a cable core being paid into an extruder comprising, A. a polygonal frame mounted across the line of advance of said core, said core passing horizontally through said frame, B. a plurality of pairs of corrugating rolls mounted on said frame in spaced positions around said core, C. payoff means for a like plurality of drain wires in fixed positions relative to said frame, D. means directing said wires between the rolls of said pairs, said rolls corrugating said wires, and E. means guiding said corrugated wires into said extruder in spaced positions around said core having the same order as the positions of the respective pairs of rolls for each wire.
 2. The apparatus of claim 1, wherein said rolls comprise radial teeth substantially exceeding in length the minimum depth of corrugation of said wires and said apparatus comprises means for limiting the depth of intermeshing of said teeth to any one of a plurality of preset positions, thereby limiting the amplitude of said corrugations to a predetermined value.
 3. The apparatus of claim 1, comprising compressed air means for separating the rolls of each of said pairs for threading said wires therebetween and thereafter returning said rolls to intermeshed positions.
 4. The apparatus of claim 1, comprising individual motors mounted on said frame driving each of said pairs of rolls.
 5. The apparatus of claim 4, comprises gang means for controlling the speed of said rolls.
 6. The apparatus of claim 5, wherein said speed controlling means comprises a voltage control of the armatures of said motors.
 7. The apparatus of claim 6, comprising means for varying the speed of each of said pairs of rolls relative to the remaining pairs.
 8. The apparatus of claim 7, wherein said speed varying means comprises motor field voltage controls.
 9. The apparatus of claim 4, comprising gang speed control means for said rolls automatically responding to changes in the speed of advance of said core.
 10. An apparatus for corrugating drain wires for a cable core being paid into an extruder comprising: A. a polygonal frame mounted across the line of advance of said core, said core passing horizontally through said frame, B. a plurality of D.C. motors mounted on said frame in spaced positions around said core, with their armatures connected in parallel, C. a like plurality of toothed corrugating rolls, each mounted to be driven by one of said motors, D. a like plurality of toothed idler rolls mounted in intermeshing relation with said corrugating rolls, E. means for separating and intermeshing said corrugating and idler rolls, F. A like plurality of fluid pressure cylinders mounted on said frame each comprising a piston actuating one of said separating and intermeshing means, G. valve means directing pressurized fluid into each of said cylinders, H. a like plurality of adjustable stops limiting the movement toward intermeshing of said idler rolls, and I. gang means for controlling the speed of all of said motors by varying the armature voltage.
 11. The apparatus of claim 10, wherein said speed controlling means automatically responds to changes in the speed of advance of said core. 